1. Field of the Invention
The present invention relates to methods of producing glass run substrates of EPDM with a urethane slip layer. The present invention further relates to molded articles having an adhesive layer.
2. Background Information
Glass runs are typically made of ethylene-propylene-diene terpolymers (hereinafter "EPDM") because of its weathering resistance, ozone resistance, heat resistance and other factors. The sliding areas of channel type glass runs, that is, a grooved bottom la and a sliding lip 1b (see FIG. 1), are provided either with a flocked layer or a urethane slip layer to lessen the glass sliding resistance (Japanese Patent Publication Nos. 62-15344 and 57-14986).
From the standpoint of lessening the glass sliding resistance, presently the flocked layer is more preferable than the urethane slip layer, however, a sliding lip with the flocked layer tends to cause wind noises.
Therefore, a channel type glass run having a flocked layer on the grooved bottom and a urethane slip layer on both sides of the sliding lip was needed and has been proposed (Japanese Utility Model Kokai Publication No. 62-161012).
However, the process to form a flocked layer and a urethane slip layer must be carried out separately, which increases the number of production processes required. Further, the adhesion is poor between EPDM substrate and the urethane coats formed of urethane coating material which is used to form the flocking layers and slip layers.
Therefore, pre-treatment of the glass sliding area is required, after the glass run substrate is extruded and vulcanized. Such pre-treatment includes, for example, buffing, degreasing and primer coating. After the urethane is coated (or after piles are spattered in case of flocked layers), the urethane coats need to be cured in a drying furnace. Such requirement affects the productivity. In addition, the continuous production system needed is significantly longer.